The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon RF 100-400mm and the Sigma 70-300mm F4-5.6 DG for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is a crucial factor to consider when comparing two lenses. Canon RF 100-400mm is the longer of the two lenses at 165mm. The Sigma 70-300mm F4-5.6 DG with a length of 122mm, is 43mm shorter. Besides being longer, the Canon RF 100-400mm also has a larger diameter of 80mm compared to the Sigma 70-300mm F4-5.6 DG's 77mm diameter.
The weight of a lens is equally significant as its external dimensions, particularly if you intend to handhold your camera and lens combination for extended periods. Sigma 70-300mm F4-5.6 DG weighs 550g, 13% (85g) lighter than the Canon RF 100-400mm's weight of 635g.
Filter Threads
The Canon RF 100-400mm has a filter size of 67mm whereas the Sigma 70-300mm F4-5.6 DG has a 58mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 67mm filters that we recommend you to consider for the Canon RF 100-400mm:
And these are the 58mm filters that we recommend for the Sigma 70-300mm F4-5.6 DG:
Lens Mounts
The Canon RF 100-400mm has the Canon RF lens mount whereas the Sigma 70-300mm F4-5.6 DG has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Canon R6 V, Canon R6 III and Canon C50 for the Canon RF Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Sigma 70-300mm F4-5.6 DG is also available in Canon EF , Nikon F (FX), Sony Alpha, Sigma SA, Canon EF, Nikon F (FX), Pentax KAF, Sony Alpha and Sigma SA mounts.
Focal Range
Canon RF 100-400mm has a focal range of 100-400mm and
4.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of
160 - 640mm.
On the other hand, the Sigma 70-300mm F4-5.6 DG has a focal range of 70-300mm and 4.3X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 105 - 450mm.
